SOIL AND WATER QUALITY MONITORING TECHINIQUES Ramesh Kanwar Professor and Chair, Agricultural & Biosystems Engineering Department Iowa State University, Ames, Iowa USA
Objectives of Soil and Water Monitoring To determine the impact of any activity on the landscape (agriculture, chemicals, manure use, industry, human or industry waste etc) on surface or groundwater quality To make sure our drinking water supplies are safe for human consumption.
Water Quality Issues Related to Human Health! Main compounds are - N, P, pathogens, and antibiotics! Surface and groundwater pollution potential! High NO 3 -N levels can cause blue baby syndrome (methemoglobinemia)! High NO 3 -N can lead to etiology of stomach cancer (only limited evidence available)! Bacteria and pathogens can be disease causing! Antibiotics as feed supplements are finding ways to water
WATER QUALITY CONCERNS FROM ANIMAL WASTES Main concern is infant health Nitrate/nitrite causes blue baby disease Newborn babies essentially suffocate Water Quality Standard for Nitrate-nitrogen is 10 mg/l SURFACE WATER WATER BODIES: Ammonia > 2 mg/l Kills Fish Phosphate > 0.05 mg/l promotes excess algae growth which leads to Fish Kills - Eutophication BOD depletes oxygen which causes Fish Kills - Hypoxia
Agricultural Contribution: World Perspective 60% N and 25% P from European Ag to North Sea 48% of nutrient pollution in the former Czechoslovakia Significant levels flowing into the Adriatic Sea Eutrophication problems in Lake Erie
NITROGEN LOSSES FROM FARMS IN THE MISSISSIPPI BASIN US Example Percent Losses Agricultural Fertilizer 55% Nitrogen from Crops 25% Non-ag fertilizers 3% Deposited by rain 15% Human Sewage 2%
Water Quality Issue: HYPOXIA The worst hypoxic conditions are in the Baltic Sea and the Black Sea Hypoxic conditions have been increasing since the 1960 s The Gulf of Mexico, outside the delta of the Mississippi River is the worlds third largest hypoxic area 12400 sq. km. (4800 sq. mi)
Major Water Quality Issue: WORLD HYPOXIC ZONES
Current Status of Iowa Lakes Mean total nitrogen for Iowa lakes sampled three times during summer, 2000 (Downing and Ramstack 2001) Slip Bluff Lak Little Sioux Park La West Okoboji Lak Arrowhead Lak Lacey Keosauqua Park La Green Belt Lak Big Spirit Lak Nine Eagles Lak Willow Lake Lake Wapell Crawford Creek Impoundme Mitchell Lak Storm Lake (incl Little Storm La Moorehead Lak Green Castle Lak Yellow Smoke Park La Red Haw Lak Pleasant Creek Lak Kent Park Lak Oldham Lake Otter Creek Lak Lake McBrid Springbrook Lak Lake Sugema Lake Anita Easter Lake Greenfield Lak Mormon Trail Lak East Okoboji Lak Three Mile Lak George Wyth Lak South Prairie Lak Blue Lake Mill Creek (Lake Lake of the Hill Hooper Area Pon Hawthorne Lake (aka Barnes City L Browns Lake Manteno Lak Twelve Mile Lak Beaver Lak Meyers Lak Arrowhead Lak Arbor Lake Dog Creek (Lake Viking Lak Upper Gar Lak DeSoto Bend Lak Spring Lake West Osceola Lake Icaria Thayer Lak Dale Maffitt Lak Fogle Lake Lake Orien Lake Minnewash Hannen Lak Rathbun Lak Avenue of the Saints La Prairie Rose Lak Lake Corneli Pierce Creek Lak Roberts Creek Lak Pollmiller Park Lak Lower Gar Lak Lake Iowa Five Island Lak Nelson Park Lak Indian Lake Lake of Three Fire Ottumwa Lagoo Lake Manaw Cold Springs Lak Diamond Lak Lake Keoma Lake Pahoja Little Rive Central Park Lak Bob White Lak Badger Creek Lak Littlefield Lak Lake Geode Clear Lake Casey Lake (aka Hickory Hills La Wilson Park Lak Green Valley Lak Lake Ahquab Lost Island Lak Windmill Lake Big Creek Lak Meadow Lak Little Spirit Lak Silver Lake Center Lake Silver Lake Silver Lake North Twin Lak Rock Creek Lak Carter Lake Williamson Pon Lake Miam Swan Lake White Oak Lak Tuttle Lake Black Hawk Lak Silver Lake Lake Smith Lake Darling Crystal Lake Lake Meye Little Wall Lak Mariposa Lak Ingham Lake East Lake (Osceola Union Grove Lak Hickory Grove La Don Williams Lak Trumbull Lake Volga Lake Briggs Woods Lak Lower Pine Lak Lake Hendrick Rodgers Park Lak Red Rock Lak Coralville Lak Upper Pine Lak Brushy Creek Lak Eldred Sherwood La Beeds Lake Saylorville Lak Badger Lake 14 12 10 8 6 4 2 0 Proposed benchmark: 700 ppb Clear Lake Crystal Lake Total Nitrogen (pp
Manure Characteristics and Production Estimates ( what does it contain) 6% of bodyweight per day (most species) 13-15 % solids 85-87% liquid
Daily Manure Production Per Animal We have estimates of manure production 4.5 kg/day/hd for swine (liquid manure) 45-50 kg/day/hd for dairy cow (liquid) 25-30 kg/day/hd for beef cow (liquid) Solid portion ~ 13-15% of total
Animal Waste Nutrient Utilization Scenario Swine Confinement Facility 4000 animals @ 61 kg / animal Nutrient Content in kg/ day / 1000 kg 0.52 kg N / day / 1000 kg animal wt. 0.18 kg P / day / 1000 kg animal wt. 0.29 kg K / day / 1000 kg animal wt.
Manure Characteristics In general Nitrogen (ammonia) is in urine Phosphorus is in feces In the U.S. we re working on ways to keep urine and feces separate
Manure Management Issues! Animal manure is a liability in high density livestock production areas where fertilizers are cheap! Animal manure is an asset if fertilizers are unavailable or expensive! Odor and ammonia emission to air-global warming! Odor issues are serious in residential areas! Pollution of soil and water resources-water quality! Hypoxia problems in international water
Nitrogen Is mobile in some forms (NO 3 ) not in others (organic, NH 4 ) Does not carryover like P Is not determined by soil test
Negative Environmental Nitrogen Impacts - Nitrates leaching to tilelines and/or groundwater - Ammonia runoff into surface water causing fish kills
Negative Environmental Impacts Phosphorus Loss with soil erosion Eutrophication (algae growth) of surface waters
Phosphorus Is bound to the soil particles Remains in the soil year to year Moves if soil erodes Is determined by soil test Does not volatilize like nitrogen
Manure Nutrient Planning Determine the hectares needed to maximize nutrient use and minimize negative environmental impacts
Question 1 Which Nutrient should I use for planning... Nitrogen? Phosphorus?
U.S. Manure Law says... Use nitrogen for nutrient planning - Results in least land area needed - May not be best use of nutrients because phosphorus is overapplied - Laws in U.S. are changing to require P planning
N:P Ratio of Manure N:P ratio is different for different types of manure N:P Cattle ratio ~ 2:1 Swine ratio ~ 1.5:1 Poultry ratio ~ 1:2
Phosphorus Planning Requires more hectares Results in lower application rates Maximize economic value of manure Depends on crop & manure application frequency Requires additional commercial N fertilizer
Question 2 How much of the nutrient should I apply??
Plant Nutrient Utilization Plant utilization Corn uses 0.7 lb/bu N 0.4 lb/bu P 2 O 5 Beans use 3.8 lb/bu N 0.8 lb/bu P 2 O 5 Plant fertilization Corn needs 1.2 lb/bu N 0.4 lb/bu P 2 O Beans need 0.0 lb/bu N 0.8 lb/bu P 2 O
Steps in Manure Nutrient Management 1. Determine crop nutrient needs 2. Determine manure nutrients available 3. Calculate hectares needed for the manure 4. Calculate manure volume to apply
Summary - Manure Planning Not difficult to do Economically advantageous Manure can replace purchased fertilizer Using manure correctly is good for the environment
Potential Pathways Pollutant Pathway Nitrate N Leaching & Runoff Ammonium N Surface water runoff & Aerial deposition Phosphorus runoff Pathogens runoff Organic Matter runoff Surface water Surface water Surface water
Soil and Water Quality Monitoring Techniques Soil sampling Surface water sampling Surface runoff Open ditch or irrigation canals Small or large rivers Ponds, lakes, reservoirs Ocean, sea Wetlands Groundwater Shallow groundwater Deep groundwater
Soil Monitoring Techniques Soil augers Soil probes Back saver Zero contamination tube Hydraulic probes